An industrial gas drive unit power migration control method, device and equipment

Abstract

The present invention provides an industrial gas drive unit power migration control method, device and equipment. The solution first calculates the gas power of the turbine compressor in real time. After the gas power is determined, it calculates the shaft power change amount when the load of the turbine compressor changes at the current moment and the previous moment of the current moment. Based on the shaft power change amount, the power and speed values of the induction motor after power migration are calculated. The speed value of the turbine expander is adjusted based on the speed value, and the surge limit line of the turbine compressor is corrected based on the speed value, so as to maintain the stable operation of the steam turbine expander and the upstream steam pipe network or the dedicated boiler, avoid the adjustment operation of the upstream steam pipe network or the dedicated boiler, and thus achieve the purpose of stable production and optimized operation.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and in particular to a power migration control method, device and equipment for an industrial gas driven unit. Background Art

[0002] In many process industries, such as petrochemical and coal chemical industries, a three-phase unit consisting of a turboexpander, a turbocompressor, and a three-phase asynchronous induction motor is used to drive process gases in factory production.

[0003] The common three-unit type is steam turbine expander + turbine compressor + three-phase asynchronous induction motor. The turbine compressor is mostly axial flow compressor, but can also be a centrifugal compressor. The three units are coaxial in operation, as shown below Figure 1 As shown. Figure 1 In the process, steam comes from the pipeline network or a dedicated boiler.

[0004] However, in actual industrial three-unit applications, the three units can only operate at rated speed. The corresponding three-phase asynchronous induction motor is connected to the grid via a switch and can only operate at the rated speed point in the motoring mode or the rated speed point in the generating mode. In other words, the three-phase asynchronous induction motor can only draw a fixed amount of electrical power from the grid, convert it into mechanical work, or output a fixed amount of electrical power and transmit it to the grid. It cannot change the magnitude and direction of the motor shaft power by changing the rotor speed n, or even flexibly migrate between the motoring and generating modes. This results in changes in the turbine compressor shaft power when the production process load driven by the turbine compressor changes. Since the three-phase asynchronous induction motor can only operate at rated speed and absorb or output a fixed amount of electrical power, to achieve stable operation of the three units, power balance can only be achieved by adjusting the steam flow entering the steam turbine expander, which is supplied by the pipeline network or a dedicated boiler. The change in the steam flow entering the steam turbine expander has a significant or even great impact on the steam production of the steam network upstream of the steam turbine expander or the dedicated boiler of the three units. Since the steam network or boiler is a typical large-delay nonlinear system, its adjustment time is long, there are many adjustment parameters, the adjustment difficulty is relatively large, and the adjustment process has a wide impact on production operations. Therefore, under the conditions of fixed shaft speed and fixed induction motor shaft power, the turbine compressor load changes due to production load fluctuations, which in turn affects the change in the amount of steam taken from the steam network or dedicated boiler by the steam turbine expander, causing disturbances and impacts on the production operations of the steam network or dedicated boiler, and leading to a series of production adjustment actions. Summary of the Invention

[0005] In view of this, embodiments of the present invention provide a method, device, and equipment for controlling the power migration of an industrial gas drive unit to maintain the stable operation of a steam turbine expander and an upstream steam pipe network or an exclusive boiler, and to avoid adjustment operations on the upstream steam pipe network or the exclusive boiler, thereby achieving the purpose of stable production and optimized operation.

[0006] To achieve the above object, embodiments of the present invention provide the following technical solutions:

[0007] An industrial gas drive unit power migration control method, the industrial gas drive unit includes a coaxial turbine expander, a turbine compressor, and an induction motor, the method includes:

[0008] Real-time calculate the gas power of the turbine compressor;

[0009] Calculate the shaft power change amount of the turbine compressor when the load changes at the current moment and the previous moment of the current moment;

[0010] Obtain the current power of the induction motor;

[0011] Based on the shaft power change amount and the current power of the induction motor, calculate the power and speed value of the induction motor after power migration;

[0012] Send the speed value of the induction motor after migration as the target speed to the speed governor of the turbine expander;

[0013] Based on the target speed, correct the surge limit line of the turbine compressor.

[0014] Optionally, in the above industrial gas drive unit power migration control method, real-time calculating the gas power of the turbine compressor includes:

[0015] Real-time obtain the operation data of the turbine compressor, the operation data includes: the process gas mass flow rate of the turbine compressor, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor

[0016] Based on the operation data of the turbine compressor, calculate the gas power of the turbine compressor by using a pre-designed calculation formula.

[0017] Optionally, in the above industrial gas drive unit power migration control method, calculating the gas power of the turbine compressor by using a pre-designed calculation formula based on the operation data of the turbine compressor includes:

[0018] Use formula J G =W*[H P +C*(T D -T S) Calculate the gas power of the turbo-compressor based on the operating data of the turbo-compressor;

[0019] Where, W is the mass flow rate of the process gas compressed by the turbo-compressor;

[0020] Hp is the polytropic head of the process gas compressed by the turbo-compressor;

[0021] C is the specific heat capacity of the compressed gas;

[0022] T D is the outlet temperature of the turbo-compressor;

[0023] T S is the inlet temperature of the turbo-compressor.

[0024] Optionally, in the above industrial gas drive unit power migration control method, calculating the shaft power change amount when the load of the turbo-compressor changes at the current moment and the previous moment of the current moment includes:

[0025] Take the gas power change amount corresponding to the current moment and the previous moment of the current moment as the shaft power change amount when the load changes at the current moment and the previous moment of the current moment.

[0026] Optionally, in the above industrial gas drive unit power migration control method, calculating the power and speed value of the induction motor after power migration based on the shaft power change amount includes:

[0027] Obtain the power-speed curve of the induction motor;

[0028] Obtain the coordinate position of the power and speed value of the induction motor at the current moment in the power-speed curve;

[0029] Take the shaft power change amount as the power change amount of the induction motor before and after migration;

[0030] Determine the power of the induction motor at the next moment based on the power change amount and the power of the induction motor at the current moment;

[0031] Calculate the speed value of the induction motor at the next moment based on the power-speed curve and the power of the induction motor at the next moment.

[0032] Optionally, in the above industrial gas drive unit power migration control method, the turbo-expander is a steam turbo-expander, the turbo-compressor is an axial-flow compressor or a centrifugal compressor, and the induction motor is a three-phase asynchronous induction motor.

[0033] An industrial gas drive unit power migration control device, the industrial gas drive unit includes a coaxial turbo-expander, a turbo-compressor and an induction motor, and the device includes:

[0034] A compressor power calculation unit for calculating the gas power of the turbocompressor in real time;

[0035] A first power change calculation unit for calculating the shaft power change of the turbocompressor when the load changes between the current moment and the previous moment of the current moment;

[0036] A target speed calculation unit for obtaining the current power of the induction motor; calculating the power and speed values of the induction motor after power migration based on the shaft power change amount and the current power of the induction motor;

[0037] An expander speed regulation unit for sending the speed value of the migrated induction motor as the target speed to the speed governor of the turboexpander;

[0038] A surge limit line correction unit for correcting the surge limit line of the turbocompressor based on the target speed.

[0039] Optionally, in the above industrial gas drive unit power migration control device, when the compressor power calculation unit calculates the gas power of the turbocompressor in real time, it specifically is used for:

[0040] Obtaining the operation data of the turbocompressor in real time, where the operation data includes: the mass flow rate of the process gas of the turbocompressor, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor

[0041] Calculating the gas power of the turbocompressor based on the operation data of the turbocompressor by using a pre-designed calculation formula.

[0042] Optionally, in the above industrial gas drive unit power migration control device, when the compressor power calculation unit calculates the gas power of the turbocompressor based on the operation data of the turbocompressor by using a pre-designed calculation formula, it specifically is used for:

[0043] Using formula J G = W * [H P + C * (T D - T S )] to calculate the gas power of the turbocompressor based on the operation data of the turbocompressor;

[0044] Wherein, W is the mass flow rate of the process gas compressed by the turbocompressor;

[0045] Hp is the polytropic head of the process gas compressed by the turbocompressor;

[0046] C is the specific heat capacity of the compressed gas;

[0047] T D is the outlet temperature of the turbo compressor;

[0048] T S is the inlet temperature of the turbo compressor.

[0049] An industrial gas drive unit power migration control device, comprising a memory and a processor;

[0050] The memory is used for storing programs;

[0051] The processor is used for executing the programs to implement each step of the industrial gas drive unit power migration control method as described in any one of the above.

[0052] Based on the above technical solutions, the above solutions provided by the embodiments of the present invention first calculate the gas power of the turbo compressor in real time. After the gas power is determined, calculate the shaft power change amount when the load of the turbo compressor changes at the current moment and the previous moment of the current moment. Based on the shaft power change amount, calculate the power and speed values of the induction motor after power migration. Based on the speed value, adjust the speed value of the turbo expander, and based on the speed, correct the surge limit line of the turbo compressor, so as to maintain the stable operation of the steam turbo expander and the upstream steam pipe network or the dedicated boiler, avoid the adjustment operation of the upstream steam pipe network or the dedicated boiler, and thus achieve the purpose of stable production and optimized operation. Description of the Drawings

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0054] Figure 1 is a unit device for driving process gas composed of a flat expander, a turbo compressor and an induction motor;

[0055] Figure 2 is a schematic flow chart of the industrial gas drive unit power migration control method disclosed in the embodiments of the present application;

[0056] Figure 3 is a schematic flow chart of the calculation of the speed value of the induction motor at the next moment disclosed in the embodiments of the present application;

[0057] Figure 4 is a schematic power-speed curve chart of the induction motor of the present application;

[0058] Figure 5Schematic diagram of the power transfer control device for an industrial gas drive unit disclosed in the embodiments of the present application;

[0059] Figure 6 Schematic diagram of the power transfer control device for an industrial gas drive unit disclosed in the embodiments of the present application. Detailed implementation manners

[0060] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0061] Turbine expander: A mechanical device that uses high-enthalpy steam or high-pressure gas with pressure potential energy to expand and then impulse a rotating turbine to do work, used to drive generators or compressor, blower, pump and other power equipment.

[0062] Turbine compressor: A type of velocity compressor with a high-speed rotating impeller. It relies on the interaction between the rotating impeller and the air flow to increase the gas pressure. At the same time, the air flow generates acceleration to obtain kinetic energy, and then the air flow decelerates in the diffuser, converting the kinetic energy into pressure energy to further increase the pressure. During the compression process, the gas flow is continuous. The turbine compressor is developed on the basis of the ventilator. It is widely used to transport air and various gases in various technological processes and increase their pressure.

[0063] Three-phase asynchronous induction motor: An AC motor that generates electromagnetic torque to drive the rotor to rotate through the interaction between the rotating magnetic field formed by the three-phase stator winding and the magnetic field of the induced current in the rotor winding. Therefore, the rotor does not require excitation. The stator winding of the AC motor can absorb electric power from the power grid and output mechanical power from the motor shaft, or absorb mechanical power from the motor shaft and output electric power from the motor stator winding to the power grid.

[0064] Slip: The percentage deviation between the synchronous speed of the power grid and the speed of the three-phase asynchronous induction motor. For a three-phase asynchronous induction motor, it can be in the generating state, at this time the slip is positive; it can also be in the motor state, at this time the slip is negative. For a three-phase asynchronous induction motor, the magnitude of the absolute value of the slip represents the magnitude of the electric power absorbed by the stator winding of the three-phase induction motor from the power grid or the electric power output to the power grid.

[0065] Surge: A unique unstable operating condition during the operation of a turbo-compressor, which can cause serious mechanical damage or destruction to the turbo-compressor. Based on the inlet operating conditions of the turbo-compressor, the operating space of the turbo-compressor is a characterized space, and its low-flow boundary is the surge limit line. Moreover, the position of the surge limit line of the turbo-compressor is affected by the rotational speed. When the rotational speed changes, in order to accurately calculate and determine the position of the surge limit line of the turbo-compressor, it is necessary to perform characteristic correction using the rotational speed.

[0066] Power migration: For a three-unit application composed of a turbo-expander, a turbo-compressor, and a three-phase asynchronous induction motor, when the load of the turbo-compressor changes, it causes a change in the shaft power of the turbo-compressor. In order to keep the output shaft power of the turbo-expander as stable as possible, by implementing the slip ratio control of the three-phase asynchronous induction motor, the change in the shaft power generated by the turbo-compressor is migrated to the three-phase asynchronous induction motor, thereby minimizing the impact on the plant power grid system.

[0067] The ideal operating mode of the three-unit is that during the steady-state operation of the three-unit shaft power at a certain power value during normal production, when the production load fluctuation causes the load fluctuation of the turbo-compressor, on the premise of ensuring the stability of the steam turbine expander power, that is, the stability of the steam consumption, the fluctuation amount of the turbo-compressor load is converted into the fluctuation amount of the shaft power through mathematical calculation, and then this converted shaft power fluctuation amount is converted into the slip change amount required by the three-phase asynchronous induction motor. By adjusting the rotational speed of the steam turbine expander to achieve the change of the rotational speed and slip of the three-phase asynchronous induction motor, while maintaining the output shaft power of the steam turbine expander basically stable, the fluctuation amount of the turbo-compressor shaft power is migrated to the three-phase asynchronous induction motor. Finally, it is reflected that under the condition of constant steam consumption and constant power of the steam turbine expander, the change amount of the turbo-compressor shaft power is resisted and absorbed by changing the rotor speed of the three-phase asynchronous induction motor to realize the rise and fall of the slip. This makes the steam network upstream of the steam turbine expander or the production of the dedicated boiler as stable as possible, thereby achieving the purpose of stable production and optimized operation.

[0068] Therefore, the present application discloses a method for controlling power migration of an industrial gas drive unit. This method calculates the change amount of the operating power of the turbo-compressor, realizes the linkage adjustment of the rotational speeds of the three units, so as to achieve the purpose of correspondingly changing the slip of the three-phase induction motor, thereby automatically migrating the change amount of the power of the turbo-compressor to the three-phase asynchronous induction motor during the production load fluctuation, and further maintaining the stable operation of the steam turbine expander and the upstream steam network or the dedicated boiler. The turbo-expander can be a steam turbine expander, the turbo-compressor can be an axial-flow compressor or a centrifugal compressor, and the induction motor can be a three-phase asynchronous induction motor.

[0069] Specifically, seeFigure 2 , the industrial gas drive unit power migration control method disclosed in the embodiments of the present application may include:

[0070] Step S101: Calculate the gas power of the turbine compressor in real time.

[0071] In this step, when calculating the gas power of the turbine compressor, it can be calculated based on the process gas mass flow rate of the turbine compressor, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor. After obtaining the process gas mass flow rate, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor, these parameters can be substituted into the preset gas power calculation model of the turbine compressor, and the gas power of the turbine compressor can be calculated based on this calculation model. Specifically, in this solution, these parameters can be substituted into formula (1), and the gas power J of the turbine compressor can be calculated through formula (1) G .

[0072] J G = W * [H P + C * (T D - T S )] Formula (1).

[0073] Among them, W is the mass flow rate of the process gas pumped by the turbine compressor, which is calculated online by the three-unit control system, and its specific calculation formula is

[0074] Among them: A is the flow coefficient of the throttling element, which is calculated from the throttling element calculation book;

[0075] △Po is the differential pressure signal detected by the throttling element, which is measured by the on-site detection transmitter;

[0076] MW is the gas molecular weight, which is obtained from the compressor parameter table;

[0077] Ps is the inlet pressure detection signal of the throttling element at the inlet, which is measured by the on-site detection transmitter;

[0078] Ro is the universal gas constant;

[0079] Zs is the inlet gas compression factor of the throttling element at the inlet, which is obtained from the compressor parameter table;

[0080] Ts is the inlet gas temperature of the throttling element at the inlet, which is measured by the on-site detection transmitter;

[0081] Hp is the polytropic head of the process gas pumped by the turbine compressor, which is calculated online by the three-unit control system, and its specific calculation formula is

[0082] Where: Rc is the compression ratio of the turbo-compressor, Rc = Pd / Ps, that is, the outlet pressure of the compressor divided by the inlet pressure;

[0083] σ is the polytropic exponent, where P S and T S are respectively the inlet pressure and inlet temperature of the turbo-compressor, measured by the field detection transmitter; P D and T D are respectively the outlet pressure and outlet temperature of the turbo-compressor, measured by the on-site detection transmitter, and the Z avg is the average value of the inlet gas compression factor of the throttling element at the inlet;

[0084] C is the specific heat capacity of the compressed gas, obtained from the compressor parameter table;

[0085] T D and T S are the outlet temperature and inlet temperature of the compressor, measured by the on-site detection transmitter;

[0086] Step S102: Calculate the change in shaft power when the load of the turbo-compressor changes at the current moment and the previous moment of the current moment.

[0087] In this step, after calculating the gas power of the turbo-compressor at each moment, based on the gas power corresponding to the current moment and the previous moment of the current moment, calculate the change in shaft power corresponding to the turbo-compressor at these two moments. At this time, the change in gas power corresponding to these two moments can be used as the change in shaft power corresponding to these two moments;

[0088] Specifically, the difference in gas power of the turbo-compressor at these two moments can be used as the change in shaft power corresponding to these two moments;

[0089] That is, substitute the gas power J G1 and J G2 corresponding to the previous and subsequent moments into formula (4) to calculate the change in shaft power ΔP corresponding to these two moments.

[0090] ΔP = J G2 - J G1 Formula (4)

[0091] When ΔP > 0, it indicates that the load power of the turbo-compressor increases; when ΔP < 0, it indicates that the load power of the turbo-compressor decreases.

[0092] Step S103: Obtain the current power and rotational speed value of the induction motor.

[0093] The current power and rotational speed values of the induction motor can be directly obtained by reading the operating condition data of the induction motor.

[0094] Step S104: Calculate the power and rotational speed values of the induction motor after power migration based on the shaft power change amount and the current power of the induction motor.

[0095] At this time, the shaft power change amount is used as the power change amount between the power of the induction motor after migration and the power of the induction motor before migration.

[0096] Step S105: Send the rotational speed value of the induction motor after migration to the speed governor of the turboexpander.

[0097] In this step, the rotational speed value of the induction motor after migration is sent to the steam turboexpander speed governor as the control target value for corresponding automatic speed increase or decrease adjustment actions.

[0098] Step S106: Correct the surge limit line SLL of the turbocompressor based on the rotational speed value of the induction motor after migration.

[0099] In this step, the rotational speed value of the induction motor after migration is denoted as N, and the surge limit line SLL of the turbocompressor is corrected using the rotational speed N. Specifically, the correction formula is as follows:

[0100] X_n2 = X_n1 * f2(N);

[0101] Y_n2 = Y_n1 * f3(N);

[0102] f2 and f3 are correction functions, and the correction functions f2 and f3 for each turbocompressor are different. The correction functions f2 and f3 for each turbocompressor can be obtained through on-site testing. The X_n2 and Y_n2 are the corrected surge limit line SLL.

[0103] After correcting the surge limit line SLL of the turbocompressor using the rotational speed N as the correction factor, the anti-surge control of the turbocompressor remains accurate and effective after the three-unit performs power migration and speed adjustment.

[0104] By implementing the above scheme disclosed in this embodiment, when the process production load fluctuates within a certain range, by automatically correcting the shaft speed of the three-unit, the shaft power change amount of the turbocompressor can be automatically migrated to the three-phase asynchronous induction motor during the production load fluctuation, thereby maintaining the stable operation of the steam turboexpander and the upstream steam pipe network or the dedicated boiler, avoiding the adjustment operations of the upstream steam pipe network or the dedicated boiler, and thus achieving the purpose of stable production and optimized operation.

[0105] In this embodiment, a specific method for calculating the power and speed values of the induction motor after power migration based on the change in shaft power is also disclosed. Refer to Figure 3 , and the method may include:

[0106] Step S301: Obtain the power-speed curve of the induction motor.

[0107] Among them, in this step, the power P-speed n curve is generated from the torque Tc-slip s curve of the induction motor.

[0108] Step S302: Obtain the coordinate position of the power and speed values of the induction motor at the current moment in the power-speed curve.

[0109] In this step, obtain the current operating point (P, n) of the induction motor, mark the current operating point on the power P-speed n curve, refer to Figure 4 , and mark the current operating point on the power P-speed n curve as "*".

[0110] Step S303: Use the change in shaft power as the power change amount of the induction motor before and after migration, and determine the power of the induction motor at the next moment based on the power change amount and the power of the induction motor at the current moment.

[0111] In this step, use the change in shaft power as the power change amount of the induction motor before and after migration, calculate the difference between the power of the induction motor at the current operating point (P, n) and the power change amount of the induction motor to obtain the operating point of the induction motor at the next moment. The actual calculation process can use the interpolation calculation function y = f(x), and mark it as "+" on the power P-speed n curve.

[0112] Step S304: Calculate the speed value of the induction motor at the next moment based on the power-speed curve and the power of the induction motor at the next moment.

[0113] After the operating point of the induction motor at the next moment, obtain the speed value corresponding to the operating point at the next moment. This speed value is the speed value of the induction motor at the next moment.

[0114] Refer to Figure 4 , Figure 4In the second quadrant, it is the power generation state of the three-phase asynchronous induction motor, and in the fourth quadrant, it is the electric state of the three-phase asynchronous induction motor. According to the positive and negative migration of the shaft power change ΔP, the rotational speed change Δn can be obtained. The rotational speed change Δn, or the rotational speed value of the induction motor at the next moment calculated based on the rotational speed change Δn and the rotational speed n of the current operating point, is directly sent to the speed governor of the steam turbine expander in the three-unit set, so that the controller can automatically adjust the rotational speed, thereby realizing the transfer of the shaft power change ΔP of the turbine compressor to the three-phase asynchronous induction motor on the premise of stabilizing the steam consumption of the steam turbine expander, and the three-phase asynchronous induction motor can perform corresponding compensation and adjustment. The three-phase asynchronous induction motor can operate flexibly in the power generation state or the electric state according to the power transfer situation. In the actual technical implementation method, the rotational speed change Δn of the three-phase asynchronous induction motor calculated by the power transfer executed according to the load power change ΔP of the turbine compressor, that is, the slip change ΔS must be within the allowable range of the three-phase asynchronous induction motor.

[0115] In this embodiment, a power transfer control device for an industrial gas drive unit is disclosed. For the specific working content of each unit in the device, please refer to the content of the above method embodiment.

[0116] The power transfer control device for the industrial gas drive unit provided by the embodiment of the present invention will be described below. The power transfer control device for the industrial gas drive unit described below can be correspondingly referred to the power transfer control method for the industrial gas drive unit described above.

[0117] See Figure 5 , the device may include:

[0118] The compressor power calculation unit A is used to calculate the gas power of the turbine compressor in real time;

[0119] The first power variable calculation unit B is used to calculate the shaft power change of the turbine compressor when the load changes at the current moment and the previous moment of the current moment;

[0120] The target speed calculation unit C is used to obtain the current power of the induction motor; calculate the power and speed value of the induction motor after power transfer based on the shaft power change and the current power of the induction motor;

[0121] The expander speed regulation unit D is used to send the rotational speed value of the induction motor after transfer as the target speed to the speed governor of the steam turbine expander;

[0122] The surge limit line correction unit E is used to correct the surge limit line of the turbine compressor based on the target speed.

[0123] Corresponding to the above method, when the compressor power calculation unit calculates the gas power of the turbocompressor in real time, it is specifically configured to:

[0124] Obtain the operation data of the turbocompressor in real time, where the operation data includes: the mass flow rate of the process gas of the turbocompressor, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor

[0125] Calculate the gas power of the turbocompressor based on the operation data of the turbocompressor by using a pre-designed calculation formula.

[0126] Corresponding to the above method, when the compressor power calculation unit calculates the gas power of the turbocompressor based on the operation data of the turbocompressor by using a pre-designed calculation formula, it is specifically configured to:

[0127] Use formula J G = W * [H P + C * (T D - T S )] to calculate the gas power of the turbocompressor based on the operation data of the turbocompressor;

[0128] where, W is the mass flow rate of the process gas pumped by the turbocompressor;

[0129] Hp is the polytropic head of the process gas pumped by the turbocompressor;

[0130] C is the specific heat capacity of the compressed gas;

[0131] T D is the outlet temperature of the turbocompressor;

[0132] T S is the inlet temperature of the turbocompressor.

[0133] Figure 6 This is the hardware structure diagram of the industrial gas drive unit power migration control device provided by the embodiments of the present invention. Refer to Figure 6 as shown, it may include: at least one processor 100, at least one communication interface 200, at least one memory 300, and at least one communication bus 400;

[0134] In the embodiments of the present invention, the number of the processor 100, the communication interface 200, the memory 300, and the communication bus 400 is at least one, and the processor 100, the communication interface 200, and the memory 300 complete mutual communication through the communication bus 400; obviously, Figure 6 the communication connection schematic diagram of the processor 100, the communication interface 200, the memory 300, and the communication bus 400 shown is only optional;

[0135] Optionally, the communication interface 200 may be an interface of a communication module, such as an interface of a GSM module;

[0136] The processor 100 may be a central processing unit (CPU), or a specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0137] The memory 300 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk memory.

[0138] Among them, the processor 100 is specifically configured to:

[0139] Calculate the gas power of the turbine compressor in real time;

[0140] Calculate the change in shaft power when the load of the turbine compressor changes between the current moment and the previous moment of the current moment;

[0141] Obtain the current power of the induction motor;

[0142] Calculate the power and speed values of the induction motor after power migration based on the change in shaft power and the current power of the induction motor;

[0143] Send the speed value of the induction motor after migration as the target speed to the speed governor of the turbine expander;

[0144] Correct the surge limit line of the turbine compressor based on the target speed.

[0145] For the convenience of description, the above system is described by dividing it into various modules according to functions. Of course, when implementing the present invention, the functions of each module can be implemented in the same or multiple software and / or hardware.

[0146] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other, and the key point of each embodiment is to illustrate the differences from other embodiments. In particular, for a system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and for the relevant parts, reference can be made to the description of the method embodiment. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without creative efforts.

[0147] Those skilled in the art can further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed in this article can be implemented by electronic hardware, computer software, or a combination of the two. To clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Skilled professionals can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0148] The steps of the method or algorithm described in combination with the embodiments disclosed in this article can be directly implemented by hardware, software modules executed by a processor, or a combination of the two. The software modules can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium well-known in the technical field.

[0149] It should also be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0150] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A power transfer control method for an industrial gas drive unit, characterized in that, The industrial gas drive unit includes a coaxial turbine expander, a turbine compressor, and an induction motor. The method includes: Calculating in real time the gas power of the turbine compressor; Calculating the change in shaft power of the turbine compressor when the load changes between the current moment and the previous moment of the current moment; Obtaining the current power of the induction motor; Calculating the power and speed value of the induction motor after power migration based on the change in shaft power and the current power of the induction motor; Sending the speed value of the induction motor after migration as the target speed to the speed governor of the turbine expander; Correcting the surge limit line of the turbine compressor based on the target speed.

2. The power transfer control method of the industrial gas drive unit according to claim 1, wherein Calculating in real time the gas power of the turbine compressor, including: Obtaining in real time the operating data of the turbine compressor, where the operating data includes: the mass flow rate of the process gas of the turbine compressor, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor Calculating the gas power of the turbine compressor based on the operating data of the turbine compressor using a pre-designed calculation formula.

3. The industrial gas drive unit power migration control method according to claim 2, wherein Calculating the gas power of the turbine compressor based on the operating data of the turbine compressor using a pre-designed calculation formula, including: Using formula J G = W * [H P + C * (T D - T S )] to calculate the gas power of the turbocompressor based on the operating data of the turbocompressor; Where W is the mass flow rate of the process gas compressed by the turbine compressor; Hp is the polytropic head of the process gas compressed by the turbine compressor; C is the specific heat capacity of the compressed gas; T D is the outlet temperature of the turbo compressor; T S is the inlet temperature of the turbo compressor.

4. The power transfer control method for an industrial gas drive unit according to claim 1, characterized in that Calculating the change in shaft power of the turbine compressor when the load changes between the current moment and the previous moment of the current moment, including: Taking the change in gas power corresponding to the current moment and the previous moment of the current moment as the change in shaft power when the load changes between the current moment and the previous moment of the current moment.

5. The power transfer control method for an industrial gas drive unit according to claim 1, wherein Calculating the power and speed value of the induction motor after power migration based on the change in shaft power, including: Obtaining the power-speed curve of the induction motor; Obtaining the coordinate position of the power and speed value of the induction motor at the current moment in the power-speed curve; Taking the change in shaft power as the change in power of the induction motor before and after migration; Determining the power of the induction motor at the next moment based on the change in power and the power of the induction motor at the current moment; Calculating the speed value of the induction motor at the next moment based on the power-speed curve and the power of the induction motor at the next moment.

6. The power transfer control method for an industrial gas drive unit according to claim 1, characterized in that, The turbine expander is a steam turbine expander, the turbine compressor is an axial flow compressor or a centrifugal compressor, and the induction motor is a three-phase asynchronous induction motor.

7. An industrial gas drive unit power migration control device, characterized in that, The industrial gas drive unit includes a coaxial turbine expander, a turbine compressor, and an induction motor. The device includes: A compressor power calculation unit for calculating in real time the gas power of the turbine compressor; A first power change calculation unit for calculating the change in shaft power of the turbine compressor when the load changes between the current moment and the previous moment of the current moment; A target speed calculation unit for obtaining the current power of the induction motor; calculating the power and speed value of the induction motor after power migration based on the change in shaft power and the current power of the induction motor; An expander speed control unit for sending the rotational speed value of the migrated induction motor as a target rotational speed to the speed governor of the turboexpander; A surge limit line correction unit for correcting the surge limit line of the turbocompressor based on the target rotational speed.

8. The power migration control device for an industrial gas drive unit according to claim 7, characterized in that, When the compressor power calculation unit calculates the gas power of the turbocompressor in real time, it specifically is used for: Obtaining the operation data of the turbocompressor in real time, where the operation data includes: the mass flow rate of the process gas of the turbocompressor, the polytropic head of the process gas, the specific heat capacity of the compressed gas, the outlet temperature of the compressor, and the inlet temperature of the compressor Calculating the gas power of the turbocompressor based on the operation data of the turbocompressor by using a pre-designed calculation formula.

9. The power transfer control device for an industrial gas drive unit according to claim 8, characterized in that When the compressor power calculation unit calculates the gas power of the turbocompressor based on the operation data of the turbocompressor by using a pre-designed calculation formula, it specifically is used for: Using formula J G = W * [H P + C * (T D - T S )] Calculate the gas power of the turbocompressor based on the operating data of the turbocompressor; Where, W is the mass flow rate of the process gas compressed by the turbocompressor; Hp is the polytropic head of the process gas compressed by the turbocompressor; C is the specific heat capacity of the compressed gas; T D is the outlet temperature of the turbo compressor; T S is the inlet temperature of the turbo compressor.

10. An industrial gas drive unit power migration control device, characterized in that, Including a memory and a processor; The memory is used for storing programs; The processor is used for executing the program to implement each step of the industrial gas drive unit power migration control method as described in any one of claims 1 - 6.

Images